Articulated coupling arrangements and slackless drawbar assemblies have been well known in the railroad industry for several years as a means to connect together the adjacently disposed ends of a pair of railway freight cars in a substantially semi-permanent fashion. In other words, these railway freight cars do not require frequent separation during service. Normally they will only be separated during a required repair and/or routine maintenance being performed on one or more of them.
These railway cars are particularly adapted for what is most commonly referred to, in the railroad industry, as piggyback service and/or dedicated service wherein the cars which are joined in such semi-permanent fashion are also commonly referred to in the railroad industry as either a "5-pack" or "10-pack" unit. These 5-pack or 10-pack units do not require the use of a standard coupler except between units. The primary reason such standard couplers are not required is because these units are only broken periodically. Normally, this occurs when maintenance and/or replacement of an individual component on one of the cars must be carried out.
Obviously, considerable cost-savings are achieved by this semi-permanent coupling arrangement. These cost savings are mainly derived from lower car weight, fewer railway trucks, reduced maintenance and generally lower equipment cost being achieved by elimination of draft gears and a reduction in the number of trucks required.
With the use of these semi-permanent coupling arrangements and with the higher loads presently being carried by modern railway trains, it is of the utmost importance that a close-buttoned relationship be maintained between the numerous coupler draft components. Such a close-buttoned relationship is required to reduce the effects of the impact forces which are encountered by a car under buff conditions of train operations.
One prior type of articulated coupling device used for the purpose of connecting adjacent ends of a pair of railway cars, in a semi-permanent manner, is taught in U.S. Pat. No. 5,172,819, the teachings of such patent hereby being incorporated into the present application by reference thereto.
This particular articulated coupling device includes a male connection member secured to one end of a first railway car body and a female connection member secured to an adjacent end of a second railway car body. The male connection member includes an aperture therein. A bearing assembly, including a substantially spherical member, is positioned within this aperture for joining the male connection member with the female connection member. A race assembly, formed by at least two members, is provided within the aperture and is positioned around a predetermined portion of the substantially spherical member.
The race assembly enables requisite movement of the male connection member in relation to the female connection member in each of a vertical direction and a horizontal direction over a predetermined range of angles measured from each of a centerline of the spherical member disposed in a vertical direction and a longitudinal axis of the articulated coupling arrangement disposed in a horizontal direction.
A securing means is provided which is engageable with each of the race assembly and the male connection member for securing the race assembly and the spherical member to the male connection member.
A typical slackless type drawbar assembly using a ball and race connection assembly comprises the following elements: a car connection member or female connection member engageable with a railway vehicle, a spherical member securable with the car connection member, a male connection member having a curved butt end and an aperture which is disposed around the spherical member secured within the car connection member and a two piece race assembly secured within the aperture of the male connection member and disposed between the spherical member and such aperture and a drawbar connected to such male connection member.
A disadvantage of the articulated coupling arrangements and slackness drawbar assemblies discussed above is the provision of at least two separate members to form the race assembly. Not only do these prior arrangements require careful machining of the separate pieces which form the race members to the correct size, but care must be taken to secure these two separate members within the aperture of the male connection member around a predetermined portion of the spherical member. These requirements add additional materials cost, assembling time and labor to the manufacture of the connection assembly of the articulated coupling arrangement and/or slackless drawbar assembly.